1. Field of Invention
The present invention relates to an illumination system including an arc tube and a reflecting mirror for reflecting the light emitted from the arc tube and a projector including the illumination system.
2. Description of Related Art
Illumination systems including an arc tube and a reflecting mirror have been widely used. In such the illumination systems, in order to make effective use of stray light that has not been used after being emitted from the arc tube, conventionally a reflective film is formed on the arc tube, as described in JP-UM-A-5-87806 (see, for example, page 7 and FIG. 1), and also a second reflecting mirror is provided to face the reflecting mirror with the arc tube therebetween, as described in JP-A-8-31382 (see, for example, page 2 and FIG. 1).